Motion control technologies can be utilized in all areas of conveyance, whether linear or rotational motion. In facilities that use systems like diverter gates, conveyor stops, pick and place, and overhead pushers, shock absorbers are central to maintaining machine reliability by dissipating the energy and reducing wear. Shock absorbers are relatively low-cost components to purchase, install and maintain as compared to the equipment they protect, and they provide additional savings to a facility by preventing machine downtime, safety concerns and potential quality issues. Investing in shock absorbers that are engineered to your facility’s unique needs and equipment cycle counts—and maintaining the shock absorbers and surrounding equipment as suggested by the user manual—is a small overall cost and time commitment for a facility that results in huge overall savings.

Small Cost, Big Savings

Shock absorbers are key to maximizing a material handling system’s speed and load, making the machine more efficient and cost effective. A custom-engineered shock absorber can save the manufacturer valuable design time and solve multiple problems economically. In certain applications like the beverage bottling industry, conveyor systems are required to quickly bring a product to a stop at regular intervals along a conveyor line in order to be cleaned, filled, sorted and packaged. The high rate of speed of the conveyor transport, coupled with the rapid deceleration of a sudden stop could result in problems for the product and the conveyor equipment if the energy is not properly absorbed throughout. It is important to custom engineer the shock absorber to the specific industry, application, machinery load and product produced. If the initial design of machinery involves the implementation of shock absorbers, it can mean high reliability and cycle time for a facility, while ensuring quality.

Maintaining the shock absorber on a regular interval ensures efficiency, avoids unexpected failures and reduces costs. Shock absorbers are adjustable based on the specific operating condition and maintaining, adjusting and replacing them accordingly is an additional step in the safe and optimal maintenance of your total assembly equipment. The shock absorber is a relatively cheap component within the larger, more expensive machine system. Lower impact forces from the motion, results in less bounce and more control over the motion. As shocks reduce the impact forces on equipment, replacing shock absorbers on schedule is an inexpensive step that will ultimately save significant long-term maintenance costs by preventing downtime and potential quality issues. Dissipating the energy and force applied to equipment parts keeps machines reliable, ensures consistency, quality output and reduces overall wear on the equipment overtime. The installation and proper maintenance of a high-class but inexpensive hydraulic shock absorber can mean big savings in overall time and costs.

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In PET bottle plants, shock absorbers are required to maintain the highest cycle rate possible while preventing damage to the bottle moulds.

Providing Added Safety

Increased productivity demands are placed on everyone in the facility, the managers, machine operators and packagers. This increased demand on staff translates to increased demand on the equipment as packaging and bottling facilities operate their assembly processes above recommended speeds, with uneven loads and in harsh environments that the original equipment may not be designed to accommodate. This puts excess strain on equipment and conveyor systems and endangers the health and welfare of employees. As machines run faster and longer, the concern for safety and the need for emergency stops is critical.

Packaging and bottling equipment manufacturers will often design equipment with shock absorption to the specifications that meet safety and industry requirements. However, when it comes to application, the end-user inevitably cranks up the speed because they want to run the machine faster to increase throughput. Shock absorbers manage the impact, or kinetic energy, of the pieces that are moving (KE = ½ m V2). Therefore, a small increase in speed means a significant increase in energy causing unplanned and unnecessary wear on the machinery and shock absorber. With the machine running faster than it should and the shocks calibrated to run at lower speeds, safety issues are presented for equipment operators. In some cases, shock absorbers aren’t designed into machinery in the first place, causing additional wear and equipment fatigue.

Shock absorbers can, and often are a retrofit solution. Ideally though, they would be designed upfront to meet the requirements of the equipment and be installed before the original equipment is used, whilst working alongside the end-user to set realistic expectations for run-time, cycle and maintenance. Custom shock absorbers can help curb safety concerns by ensuring the extra daily force is being dissipated appropriately instead of being pushed through machine components, avoiding failures, and equipment can be slowed and stopped safely, if an emergency does happen.

Decreasing Downtime No Matter the Industry

With today’s tight time constraints and ambitious production goals, shutting down a production line altogether can prove very expensive. For industries like packaging, food and beverage and PET bottling, machinery and its components also need to withstand environments like frequent wash down and high temperatures, while operating at a high cycle rate. As shock absorbers protect against excess force and prevent additional wear and tear, they can help minimize component failure and help machines operate at their highest capacity. Designing shock absorbers into the equipment is key in meeting unique requirements, whether a bottling facility requires specific location sensors or a food packaging plant needs components that operate in small spaces and unique wash-down environments. Downtime due to component failure is minimized, allowing equipment to operate at design conditions.

For example, a packaging systems manufacturer produces a variety of machines that package food products such as deli and sausage products. One of these packaging machines was specifically used to package poultry products. During operation, this machine needs to withstand the wet and messy environment of poultry packaging, including frequent wash down. As a market leader, the company needed this machine to operate at the fastest cycle rate in the industry. This means that each machine must process 15 to 18 birds per minute. The machine was designed with shock absorbers installed at the end-of-stroke position on a pneumatic rodless cylinder used for a shuttle operation and at-the-end of cycle position as a positive stop for a pivot. Unfortunately, the pre-installed shock absorbers could not withstand the high cycle rate or harsh environment.

ITT Enidine worked with the company to design a special shock absorber that would withstand the cycle rate, processing environment and frequent wash down. The solution was custom-engineered to have a substantially higher capacity and a smaller envelope than pre-installed, competing shock absorbers. With the new solution, downtime due to component failure was minimized and the packaging machines operated at optimal cycle rates. Because of this productivity increase, the company maintained its market position and increased sales annually. Packaging machines are excellent candidates for shock absorption technology, which control air cylinders and help machines operate at their highest capacity.

Ensuring Quality and Reliability

Shock absorbers can improve the overall quality of equipment by meeting the necessary environmental needs, like extreme heat or cold, production speed and uneven loading. Custom engineering of a shock absorber for each unique application will allow that shock absorber to work specific to that application. Regular equipment maintenance, including replacement of shock absorber, is key to keeping machinery running at its highest potential to ensure quality and reliability throughout the production process.

In PET bottle plants, shock absorbers can create efficiencies and protect equipment in applications like blow moulding, case packing, carton forming or container labelling. The machines that are used to create today’s PET bottles—typically made of a high-gloss, crack resistant plastic known as Polyethylene Terephthalate (PET)—have the highest production rates in the industry and are referred to as blow moulding machines. The equipment consists of multiple “clam shell” moulds placed around a vertical axis, rotated in a horizontal plane. The rotated plane creates centrifugal force to move the plastic material within the mould cavity, creating the bottle shape. Shock absorbers are required to maintain the highest cycle rate possible while preventing damage to the opening and closing of the clamshell.

In cases like PET bottle plants, shock absorbers are central to ensuring quality and reliability. By scheduling maintenance and proper replacement parts, facilities will see an increase in performance and durability in applications that encounter uneven loading, bending or harsh environments. Ultimately, this equipment protection results in increased safety, efficiency and product quality, while decreasing downtime and cost.

Author: Dieter Klaiber, Project & Application Manager, ITT Enidine Europe, dieter.klaiber@itt.com